#include<stdio.h>
#include<assert.h>
char* my_strstr(const char* arr1, const char* arr2)
{
	assert(arr1 && arr2);
	const char* s1 = arr1;
	const char* p = arr1;
	const char* s2 = arr2;
	while (*p)
	{
		s1 = p;
		s2 = arr2;
		while (*s1 == *s2 && *s1 != '\0' && *s2 != '\0')
		{
			s1++;
			s2++;
		}
		if (*s2 == '\0')
		{
			return p;
		}
		p++;
	}
	return NULL;

}
int main()
{
	char str1[] = "abbbbcdef";
	char str2[] = "bbc";
	char* ret = my_strstr(str1, str2);
	if (ret == NULL)
	{
		printf("NULL\n");
	}
	else
		printf("%s", ret);
	return 0;
}